Kin Selection

Question 1

Behavioral ecology 2 basic themes

Answer 1

• natural selection acts on behavior. Result is to produce behavior which is adaptive
• optimality: is philosophical position that organisms over time should have developed behavior that maximizes their fitness

Question 2

Altruism

Answer 2

Behavior that increases fitness of another individual at the expense of ones own fitness

• if altruistic behavior is costly, genes promoting it should disappear from population
• even if important, genes coding for selfish behavior should spread and displace altruistis
• self sacrifice behavior abounds
• most selfless are ants bees and wasps

Question 3

Behavior explained:

Answer 3

Individuals sometimes communicate their awareness of predators (alarm calls, whistling etc)

Question 4

Components of group size

Answer 4

1. many eyes effect
2. dilution effect
3. Attraction effect

Question 5

W.D Hamilton argued…

Answer 5

Altruism evolves if individuals increase their “inclusive fitness” that is the proportion of their genes carried by others in the population.

Question 6

Under hamiltons rule, fitness has 2 components

Answer 6

1. direct fitness: reproductive success of the individual (has own offspring and their offspring)
2. indirect fitness: reproductive success of an individuals relatives

Inclusive fitness: direct + indirect fitness

Question 7

Hamiltons kin election theory

Answer 7

• some behavior have evolved to increase fitness of org. Close relative
• individuals might have alleles that code for behaviors that help close relatives raise more offspring than they would without help
• these favored by kin selection, close relatives are likely to have copies of the same heritable traits

Evolves: Br>C
B= benefit to relative
r=cost of behavior in terms of ones own fitness
C=cost of behavior in terms of ones own fitness

Question 8

Coefficient of relatedness

Answer 8

Probability that an allele is shared as a result of having a common relative

Question 9

Reciprocal altruism

Conditions:

Answer 9

Altruistic behavior, among non-relatives revolve only when such actions lead to reciprocal beneficial actions in future
-you scratch my back. I scratch yours.

1. Cost must be less than benefits of receiving help
2. donors must be able to recognize cheaters
3. must be many opputunities for interactions between individuals